Undoubtedly, the prevalence of farmers markets and thoughtfully curated seasonal menus have inspired customers to think twice about their eating habits, and altered the landscape of the American dining scene, yet fast food — whether eaten out of desperation on a long interstate haul, or indulged in as cheap convenience when a craving for french fries strikes — continues to resonate with Americans, as this list of the top nine revenue-earning chains reveals.

Although sandwich behemoth Subway is the country’s second highest-grossing chain (and has more outposts than any other with more than 24,000 throughout the country as of Feb. 16, 2012), it trails behind McDonald’s considerably, at $10.6 billion (by year-end December 2010). Burger King rounds out the top three with $8.4 billion (by year-end June 2011), and the success of the popular "My 99¢ Everyday Value Menu" may have helped Wendy’s land the number-five slot at $7.9 billion (by year-end December 2010).

Americans also relish their coffee (and sweet treats) on the go. The ubiquitous Starbucks came in at number four, with $8 billion earned (by year-end September 2010), while Dunkin’ Donuts found its way to number seven at $5.4 billion (by year-end December 2010).

Yum! Brands also snagged three spots: Taco Bell at number six with $6.9 billion, Pizza Hut at number eight with $5.4 billion, and KFC at number nine with $4.7 billion (all by year-end December 2010.)

What keeps patrons coming back to these familiar fast-food restaurants? Take a look at what’s new (and in the works) at America’s highest-grossing chains.